CONCORD, N.H. — Mitt Romney's presidential campaign is shifting into a new gear.

The Republican has spent much of the year laying low — so much that more than three weeks have passed since he last held a campaign event in New Hampshire.

His pace is starting to accelerate. The GOP front-runner made three stops in the first-in-the-nation primary state Monday and will return five more times before the end of the month. Aides said to expect more visits in Iowa and Florida, too.

Romney also is getting more aggressive with his message. That showed Monday, when he launched into a blistering critique of President Barack Obama on the nation's debt. He accused Obama of blaming other people for the woes.

Romney himself has been criticized as absent from the debt-ceiling debate.